1. Technical Field
The present invention relates to an art for carrying out a so-called direct printing using a host device of a printer which operates on a single task OS.
2. Related Art
There is an art of a so-called direct printing in which a digital camera or the like is directly connected to a printer, and the digital camera, being used as an image source apparatus, sends image data to the printer, and causes the printer to print them. A representative standard in the direct printing is PictBridge.
In a case of carrying out the direct printing by using the PictBridge, in the event that there is an instruction to acquire a printer's Capability, which is a specification related to the printing by the printer, from a high order application, a PictBridge driver issues a DPS_GetCapability command to the printer, and acquires the printer's Capability (for example, JP-A-2005-88572).
However, in the technique of JP-A-2005-88572, as, on receiving a Capability acquisition command from the high order application, the PictBridge driver carries out a DPS_GetCapability operation, unless the high order application is notified that there has been a response of DPS_ConfigurePrintService which should be made prior to the DPS_GetCapability operation, the Capability acquisition command from the high order application is not issued. That is, for as long as the high order application is not notified that there has been the response of DPS_ConfigurePrintService, the high order application continues to await the response.
Furthermore, the CPS_GetCapability command is issued to the printer a number of times but, when, on receiving the Capability acquisition command from the high order application, the PictBridge driver issues the DPS_GetCapability command, unless there is a response thereto, a next Capability acquisition command is not issued either, and the high order application continues to await the response.
In the event of the heretofore described kind of situation, no problem arises when the high order application and the PictBridge driver operate on separate tasks but, for example, in a case in which they operate on an identical task as on a single task OS, as the high order application occupies the OS until there is a response from the printer, all processes in the image source apparatus are stopped.